Air cooled unit air conditioner



4 She ets-Sheet l IN VENTOR RichardEBoseman ATTORNEYS R. E. ROSEMAN w vNo w. 9 r, L; nnnduuwu liliEILLILJ Feb. 12, 1957 AIR COOLED UNIT AIRCONDITIONER --------------&

Feb. 12, 1957 R. E. ROSEMAN AIR COQLED UNIT AIR CONDITIONER 4Sheets-Sheet 2 Filed March 7, 1956 INVENTOR Richard. ERoseman ATTORNEYS12, 5 R.- E. ROSEMAN AIR COOLED UNIT AIR CONDITIONER 4 Sheets-Sheet 3Filed March 7, 1956 Pic-3.3

BY a iwin ATTORNEYS 5 Feb'.12',1957 R'E. ROSEMAN 2,780,929

AIR COOLED UNIT AIR CONDITIONER Filed March 7, 1956. 4 Sheets-Sheet 4Richar dERoseman ATTORNEYS INVENTOR AIR COOLED UNIT AIR CONDITIONERRichard E. Roseman, York, Pa., assignor, by mesne assignments, toBorg-Warner Corporation, Chicago, 111., a corporation of IllinoisApplication March 7, 1956, Serial No. 570,111 8 Claims. (Cl. 62129) Thisinvention relates to air conditioners of the type in which the machinehousing is wholly within the room against the wall and spaced above thefloor, the machine being suspended by the condenser air duct which restson a window sill and reaches not quite to the inner plane of the lowersash (assuming a double hung window).

This arrangement has a number of outstanding advantages particularly ascompared with conventional consoles. The condenser air duct need not beadjustable. The lower sash can be closed and locked while the machine isin position (but shut down). The obstruction of the window is only forthe height of the condenser air duct and condenser plenum. The entiremachine is completely protected from the weather when the window isclosed and only slightly exposed when the window is open. The unit isadaptable to use with casement windows. It may be wholly or partlyrecessed in the-wall and pass the condenser air streams through anopening in the wall provided for that purpose. Finally installation andremoval are safe and easy to perform.

Units having such a combination of qualities were not practicable untilit became possible to reduce greatly the size and weight of the unit.This has now been done, and the cubage of the present one horsepowerunit is less than half that of a commercial floor mounted one horsepowerconsole which it replaces. While part of the advantage arises from thehigh efficiency hermetic compressor, significant space-saving comes frommounting this with its shaft vertical. Great economy of space is had bythe use of a new duplex variable speed fan unit, characterized bylarge-diameter single-eye runners of short axial dimension mounted inlarge diameter snail shell housings. Finally the mounting of theheat-exchangers (condenser and evaporator) at the top of the unit,immediately above the fans and extending horizontally parallel with eachother and with the wall, saves space and reduces the problem ofdrip-disposal to the ultimate of simplicity.

Closely related to the mounting of the evaporator and condenser is theuse of a longitudinal vertical partition, parallel with the wall of theroom, to divide the space within the main housing into two spaces onecontaining the evaporator fan and the other containing the condenserfan. These spaces underlie respective plenum spaces.

Removal of the front panel gives direct access to the front space and tothe entire machine, except the condenser fan runner, and reveals thefact that the available space is efficiently utilized, but notobjectionably crowded. For example, in the illustrated preferredembodiment, the snail shell fan housings discharge directly into theplenum spaces which respectively enclose the condenser and evaporator.Internal duct work is conspicuously absent.

The fan motor has been described as variable in speed. Slowing the fansincreases the latent heat cooling of room air but reduces the totalrefrigerative eifect. Since the condenser fan and the evaporator fan aredriven in unison the system remains nearly enough in balance to preventF ice freeze-ups, even at slower speed. Somewhat similar controls havebeen used in the past, but as used heretofore, slowing of the evaporatorfan reduced the velocity of air discharge into the room, with attendantimpairment of the induced room-air circulation. In the conditioner aboutto be described, air leaving the evaporator passes through an adjustabletapering nozzle extending the width or the machine. The fan speedcontrol and the means for adjusting nozzle taper are so interconnectedthat as the fan is slowed, and hence as less air is discharged into theroom, the nozzle is constricted so as to maintain the velocity of airdischarge at a useful level, and preferably substantially unchanged.

The invention will now be described by reference to the accompanyingdrawings which show one commercial embodiment. In the drawings:

Fig. 1 is a front elevation of the machine as it appears with the lowerfront panel removed.

Fig. 2 is a section on the line 2-2 of Fig. 1.

Fig. 3 is a section on the line 3-3 of Fig. 1.

Fig. 4 is a perspective view of the main housing with the snail shellfan housings in place. The dampers which control the flows of fresh andrecirculated air are shown. The pump-out opening is shown, but not theadjustable damper which controls it.

Fig. 5 is a perspective view of the pump-out opening, with its damper,the fresh air opening with its damper, the related return air damper(which controls inflow through an open portion of the bottom of the mainhousing), and two manual damper-controls.

Fig. 6 is a wiring diagram for the fan control.

In these views conventional sound insulating linings and coatings areomitted, though they are used.

In the above views, some details not of patentable moment have beenomitted, to simplify the disclosure. Selection of satisfactoryexpedients is within the skill of the art.

The main housing (see particularly Fig. 4) comprises end plates 11 and12, a back plate 13 which is curved over to form the bottom of thecondenser air inlet passage 14 (see Figs. 2 and 3). A vertical crosspartition 15 forward of a longitudinal partition 16 divides thecompressor space from the evaporator fan space. The longitudinalvertical partition 16 extends between end plate 11 and the rear edge ofthe cross partition 15 and divides the evaporator fan space at the frontof the machine from the condenser fan space which is at the rear. Asviewed in plan the compressor space and the condenser fan space form asingle L-shaped chamber. The partition 16 is one of the most significantand distinctive features of the invention and has led to remarkablesimplicity-of form with attendant saving of space and material.

The evaporator fan space and the compressor space are separated by ahorizontal pan 17 from the evaporator plenum which is immediatelyabovecthe pan. A horizontal partition 18, at a higher level than pan 17forms the bottom of the condenser plenum, overlies the condenser fanspace and is connected with the end plates 11, 12. The inclined upperportion 19 of partition 16 above horizontal partition 18 separates theevaporator plenum from the condenser plenum.

The snail shell 21 for the evaporator fan and the snail shell 22 for thecondenser fan are mirror duplicates except that shell 22 has a somewhatlonger discharge neck 23 to reach the condenser air opening formedthrough the partition 18 which is at a higher level. The shell 21 has ashorter neck 24 which reaches through the evaporator air opening in theevaporator drip pan 17. This opening has an upstanding rim 25 for waterretention purposes. It should be observed that the partition 16 extendsup to and is connected with partition 18, and though the portion 3 of itbelow pan 17 ends at partition 15, there is an extension 26 above pan 17which extends from partition to end plate 12. In this extension 26 thepump-out opening 27 is formed. i i

It is convenient structurally, to have the two snail-shell housingsmirror duplicates supported by the partition 16, but they need not be.They could difier in dimension and be otherwise supported. Theillustrated Construction has obvious advantages.

As best shown in Fig. 2 the bottom of the main housing forward ofpartition 16 and between partition 15 and end plate 11, is open toafford a return-air passage indicated at 28. Flow through this can bemodulated by adjusting damper 29 which is hinged at its lower edge tomove from its fully open position shown in Fig. 2 to a flow restrictingposition in which its free, upper edge is against snail shell 21. Inthis last setting it does not completely close the return-air inlet.Damper 29 is actuated by the fresh air damper 31 which is hinged at 32to partition 15 "and controls a port 33 through that partition. Thedampers are connected by a pin 34 on damper 31 working in a slot 35carried by damper 29.

As damper 31 moves from closed position in its opening direction, damper29 is moved in its closing direction. This permits proportioning themixture of fresh and recirculated air. Damper 31 is actuated by lever 36through the Bowden wire unit 37. Lever 36 is in a space 38 to the rightof the evaporator plenum. A second lever 39, also in space 38 isconnected by a Bowden wire unit 41 with the hinged pump-out damper 42.

Opening of damper 31 connects the air inlet passage 14 through thecondenser fan spaced behindi'partition 16 and thence through thecompressor space to the left of partition 15 with the inlet eye ofevaporator fan 21. Opening of damper 42 connects the discharge side ofevaporator fan 21 with the inlet eye of condenser fan 22 so that thefans act in series and a'rapid pump-out is assured.

In snail shell 21 there is a single-eye runner 43 whose radial dimensiongreatly exceeds its axial dimension. Similarly in snail shell 22 thereis a single-eye runner 44 whose dimensions in the example illustratedare appm imately the same as those of the runner 43. The two runners aremounted back to back on a drive shaft 45 which is driven by a variablespeed motor 46. The motor 46 is hung in a bracket 47 beneath the drippan 17. This is considered the simplest possible way to drive the fanrunners in unison, but the same effect can be secured in other ways. Thesignificant fact is that they are driven in unison.

The snail shells 21, 22 have each an entrance shroud ring 48. Thesefavor smooth flow to the corresponding fan runner. Removability isnecessary to permit removal of the corresponding runner. The dischargeneck 23 of snail shell 22 delivers condenser cooling air directly intothe space above horizontal partition 18. This is the combined condenserplenum and condenser air discharge duct. It is closed at the top byplate 49. and it and the duct 14 terminate in a plane vertical open facespaced inward a short distance from the plane of the inner face of thewindow sash. To fill out the portionsof the window opening at the sidesof the structure which encloses the condenser air paths some windowboard or other conventional closure (not illustrated) would be used.

'A finned tubular condenser 51 i s fmounted above partition 18 in thepath of discharging air. i

Above pan 17.is the evaporator plenum of which the back is defined byplate 19, thetop by plate 52am the ends by the end plates 11 and 12 oftheitnain housing. The evaporator 53 is of the finned tubular type andoverlies the front portionof pa njli Thc parifeollects the drip. waterresulting from dehuinidification of air. Snail s'he'll21 discharges intothe space behind. evaporator 53 and air discharginigthetrefrom vflout/"sfiist 54 set- 9 t we il et-a hes? "r lates wi h t evaporator tubes; The'filter 54 is'mounted in edge guides 55 and may bewithdrawn upward. Ahinged cover 56 may be opened to give access to the filter, and also tocontrols, such as the damper levers 36 and 39 which are illustrated andother conventional controls which are not shown (such as the compressorswitch and adjusting means for a thermostatic controller, when used, andthe like). A removable panel 59 closes the front of the housing.

Air, cooled and dehumidified by heat exchange with evaporator 53,discharges at the front of the evaporator. It is desired that this airdischarge upward at considerable velocity so as to induce aircirculation in the room and assure immediate tempering of the cold dryair by mixture with the room air. To this end, a door or bafi le 57hinged at 58 along its lower edge to the main housing, forms theadjustable front member of an air-discharge nozzle.

There is an optimum value for the velocity of air discharge, and to keepthe discharge velocity at or near this value the door 57 is connectedwith means to vary the speed at which at least fan runner 43 is driven.With a constant speed fan, restriction of the nozzle would tend toincrease the velocity of discharging air. To neutralize this tendencymeans are provided to slow the fan as the nozzle front 57 moves in aclosing direction. As a practical matter this has to be done in stepswhen the fan runner is electrically driven. Hence the door 57 carries alug 60 projecting below the axis on which the door is hinged to engagethe actuator 61 of a toggle switch which controls the speed of motor 46.The control circuit is diagrammed in Fig. 6, and the toggle switch isthere shown in plan.

In Fig. 6 two field windings of motor 46 are indicated at 7 1 and 72.The switch, which is of known commercial form, has a movable contactor73 which shifts to close selectively against contacts 74 and 75, areversing bias being afforded by the spring 76.

When door 57 is drawn forward to open the nozzle wide, lug 60 movesinward and shifts actuator 61 inward. Contactor 73 closes againstcontact 74. Only winding 71 is in circuit and the fan motor 46 runs atfull speed. When the door 57 is partly closed and the nozzle slot isrestricted lug 60 has moved forward permitting actuator 61 to moveforward. The switch contactor 73 engages contact 75, both windings 72and 71 are in circuit and the fan motor 46 operates at reduced speed.Two speeds illustrate the principle, and ordinarily are sufficient. Morecan be provided by means familiar in the motor control art, shouldcloser graduation be desired.

The control is so proportioned that the velocity of air discharging fromthe nozzle remains uniform, so that the room air is induced to circulateat an acceptable rate.

The condenser 51, and evaporator 53 are connected in a compressor,condenser evaporator circuit with the hermetically sealed compressor 62.To control flow of liquid refrigerant from the condenser to theevaporator, use is made of a fixed restrictor (not shown), so that thecompressor is the only moving part in the circuit. Such circuits are inextensive use in the conditioner art and hence detailed illustration anddescription are not needed.

Water condenses from the air on evaporator 53 and drips to pan 17,whence it drains via port 64 and tube 65 into the condenser fan snailshell 22, and is carried upward by the air stream to condenser 51 whereit is reevaporated and blown out-of-doors with the condenser air. If anywater precipitates on partition 13 from any source it drains via port 66and drain tube 67 to the condenser fan snail shell to be sprayed by thecondenser fan runner. Various schemes to improve the spraying of drip bya condenser fan are known, and any preferred one may be used.

The basic operative principle of the conditionerconforms to well knownpractice. Air, drawn from the room by the evaporator fan either alone ormixed with air from out, ofdoors, is forced to flow in heat-exchangerelation with the evaporator and then is discharged into the room insuch direction and at such velocity that circulation in the room isstimulated, and the cold dry air leaving the evaporator is tempered bymixture with room air.

At the same time, air drawn from out of doors is circulated inheat-exchange relation with the condenser. This air, after exchange ofheat with the condenser, is discharged out of doors. Drip water whichcondenses on the evaporator is fed to the condenser air stream and isthere re-evaporated by heat from the condenser. As a consequence, boththe heat and the moisture which are withdrawn from the conditioned spaceare removed by way of the condenser air stream.

The most important aspect of the invention is a coordinated arrangementof the essential components of a unit air conditioner, to utilizeefiectively the space within the housing while giving that housingproportions which render it reasonably inconspicuous and adapt it tomounting upon a Window sill or beneath a window of conventional form.Modifications of proportion are obviously possible, but the arrangementshown is based on a long and careful study of the problem, and isbelieved to mark a substantial advance in the art.

What is claimed is:

1. For use in a room adjacent a Wall having an opening to externalspace, an air conditioner comprising in combination a housing which(described with reference to its operative position) is substantially aparallelepiped closely adjacent the wall and of small horizontaldimension measured away from the wall and of larger vertical andhorizontal dimensions parallel with the wall, said housing having anextension subdivided into two ducts for communicating with externalspace through the wall opening, said housing being divided by asubstantially vertical partition approximately parallel with the wallinto a roomair circuit space remote from the wall, and a condenseraircircuit space adjacent said wall, there also being within said housingmeans dividing the room-air circuit space into a fan chamber having aninlet from the room, and an evaporator plenum space having an airdischarge to the room and there being also within said housing meansdividing the condenser-air circuit space into a fan chamber having aninlet passage from external space through one of said ducts in saidextension and a condenser plenum space having an exit through the otherduct in said extension; two fans each comprising a rotary impeller whosediameter is a multiple of its axial dimension and an enclosing housing,said fans being mounted in respective fan chambers each to receive airfrom its fan chamber and discharge it through the corresponding plenumspace, the axes of the fan impellers being horizontal and substantiallynormal to said vertical partition; means for driving said fans; and arefrigeration circuit comprising an evaporator enclosed in saidevaporator plenum space in the path of room air flowing therethrough anda condenser in said condenser plenum space in the path of external aircirculated therethrough.

2. A conditioner as defined in claim 1, in which the rotary impellers ofthe two fans are mounted on a motordriven shaft which extends throughthe vertical partition first named.

3. A conditioner as defined in claim 1 in which the rotary impellers ofthe two fans are mounted on a motordriven shaft which extends throughthe vertical partition first-named; and each fan impeller is enclosed ina corresponding volute shell, the two shells having their proximatefaces on opposite sides of said vertical partition, each volute shellhaving an entrance eye remote from said partition.

4. A conditioner as defined in claim 1 in which the rotary impellers ofthe two fans are mounted on a shaft which extends through the verticalpartition first-named; each fan impeller is enclosed in a correspondingvolute shell, the two shells having their proximate faces on oppositesides of said vertical partition, each volute shell having an entranceeye remote from said partition; and the means for driving said fanscomprises a motor at least partially received within the eye of one ofsaid fans.

5. A conditioner as defined in claim 1 in which the evaporator plenumspace is horizontal, elongated and wholly above the top of thecorresponding fan; and the condenser plenum space is within the exitduct in said extension.

6. In an air conditioner, the combination of a cooling unit; a fan forcirculating air into heat-exchanging relation with said unit and thendischarging it into a space to be conditioned; a slot nozzle throughwhich said discharge occurs, said nozzle discharging the air in adirection and at a velocity which will induce air circulation in thespace to be conditioned, and the nozzle including a part movable toadjust the area of its slot; a variablespeed motor connected to drivesaid fan; a controller operable to change the speed of the motor; and aconnection between the movable part of the nozzle and said controllersuch that the motor is slowed when the nozzle opening is reduced.

7. In an air conditioner, the combination of a cooling unit; a fan forcirculating air in heat-exchanging relation with said unit and thendischarging it into a space to be conditioned; restricting means throughwhich said discharge occurs, said restricting means discharging the airat a velocity to induce air circulation in the space to be conditioned;means for varying the weight of air per unit of time which is dischargedthrough the restricting means into the space to be conditioned; andmeans responsive to said varying means for maintaining said dischargevelocity substantially constant.

8. In a refrigerative air conditioner for a space to be conditioned, thecombination of a condenser; an evaporator; a main housing enclosing thecondenser and evaporator, said housing having a partition segregatingsaid condenser and evaporator; dual fan means mounted in said housing onopposite sides of said partition for circulating cooling air throughsaid condenser to an external space and air to be conditioned throughsaid evaporator to said space to be conditioned; and means for varyingthe air delivery rate of said fans while maintaining the velocity ofsaid air at the point of discharge into said conditioned spacesubstantially constant.

References Cited in the file of this patent UNITED STATES PATENTS2,185,387 Weiland Jan. 2, 1940 2,343,121 Eberhart Feb. 29, 19442,753,699 Gannon July 10, 1956

